Of X-ray imaging apparatuses, a mammography apparatus is an apparatus that irradiates X-rays to a breast and detects the X-rays penetrating through the breast to obtain a projection image, which allows early detection of a lesion such as breast cancer through the projection image. Here, radiography is performed with the breast compressed using the compression paddle, so that a lesion such as breast cancer does not overlap with the mammary gland.
However, if an emergency occurs during x-ray imaging (that is, during the breast is compressed by the compression paddle), for example, when a power supply is interrupted, a patient may feel uneasiness with the pain due to the continuous pressure on the breast.
To solve the above problem, for example, Korean patent application publication No. 10-2013-0077793 (published Jul. 9, 2013) discloses a conventional X-ray imaging apparatus.
The conventional X-ray imaging apparatus includes an electromagnetic clutch capable of selectively interlocking/disengaging the drive of the mobile device and the movement of the compression paddle according to the power on/off, wherein the electromagnetic clutch serves to release the compression of the compression paddle on the breast in an emergency such as power failure (i.e. the power is cut off).
However, in the conventional electromagnetic clutch, it serves as a means for releasing compression in the case of a complete interruption of the power supply such as due to a power failure, but it fails to serve as the means for releasing compression in the case where it is necessary to release the compression of the compression paddle on the breast due to instability of a power supply.
Meanwhile, the conventional X-ray imaging apparatus is controlled such that a compression force of the compression paddle on the breast is determined according to a predetermined manual value or is determined based on a detection result by detecting a repulsive force of the breast.
However, the conventional X-ray imaging apparatus is problematic in that since the degree of pain experienced by the patient due to the compression of the compression paddle on the breast varies with a biometric index such as patient age, breast size, and breast density, when the compression force of the compression paddle is determined solely on the basis of the uniform manual value or the repulsive force of the breast, whereby the patient is greatly distressed by the compression of the compression paddle during the radiography, and it is impossible to obtain a clear projection image of the breast when the patient is moved due to the pain, and as a result, it is impossible to identify a breast lesion correctly.